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Cesium Chloride

Crystal: CsCl Structure: CsCl

(Crystal b -CsCl Structure: NaCl)

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Mechanical and structural properties:

Lattice formation energy:	-6.61 eV. (theory, Mayer et al.) (Ref.1)
	-6.56 (experimental) (Ref.1)
Lattice parameter:	3.56 Å for CsCl
	(3.51 Å for b -CsCl)
Density:	g/cm³

Stiffness constants: in 10¹¹ dynes/cm², at room temperature

c₁₁: 3.64 or 3.683 (Ref.2)

c₁₂: 0.92 or 0.893

c₄₄: 0.80 or 0.817

Compressibility (in 10¹¹ dynes/cm²): 0.547 ??

Poisson ratio:

Debye temperature: K

Melting temperature: K

Phonon spectrum discussed by:

J.F. Vetelino, Lattice dynamics, mode Gruneisen parameters & coefficient of thermal expansion of CsCl, CsBr & CsI, Phys. Rev. B2, 2167 (1970)

Also: A.A.Z. Ahmad, H.G. Smith N. Wakayashi & M.K. Wilkinson, Lattice dynamics of Cesium Chloride, Phys.Rev. B6, 3956 (1972)

Transverse optic phonon T0 (k=0): 99 cm^-1

Longitude optic phonon L0 (k=0): cm^-1

Gruneissen constant:

Ratio e*/e: 0.85

Photoelastic constants:

p₁₁:

p₁₂:

p₄₄:

Electronic properties:

Band gap:

direct: eV. at K

indirect: eV. at ° K

Plasmon energy: eV.

Exciton energy: 7.85 eV. (Ref.3)

Band structure discussed by:

L. Nosenzo & E. Reguzzoni, Analysis of the electronic structure in Cesium halides by deflectance & thermoreflectance studies,Phys.Rev.B19,2319 (1979)

Also: E. Boursey and J.-Y. Rongin, Absorption spectra of Cesium halides at 20K. from 12 to 20 eV., Sol. State Com. 9, 1049 (1971)

Static dielectric constant: 7.20

Optic dielectric constant: 2.60

Electron mobility:

Hole mobility:

Polaron coupling constant: a = 6.3 ( for m*=1 )

Effective mass:

conduction band:

valence band:

Electron affinity: ( in eV., from bottom of conduction band under vacuum)

Spin-orbit coupling: ( valence band)

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References:

1. C. Kittel, "Introduction to Solid State Physics", 2nd. Edition, New York: Wiley (1956)

2. Ted R. Musgrave, "Understanding problems for chemical principles", Philadelphia: Saunders (1978)

3. W.B. Fowler, "Physics of Color Centers", New York: Academic Press (1968)

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